The leg tuck was replaced by the plank in the Army Combat Fitness Test, in part because it was felt it discriminated against women. There is limited leg tuck research, including between-sex comparisons and relationships with other fitness tests. This study investigated the leg tuck in a firefighter trainee population (274 males, 31 females). Archival fitness test data included: Illinois agility test (IAT); push-ups; pull-ups; leg tucks; multistage fitness test; 4.54 kg backwards overhead medicine ball throw (BOMBT); 10-repetition maximum deadlift; and 18 kg kettlebell farmer's carry over a 91.44 m course. Independent samples t-tests (p < 0.05) and effect sizes (d) compared the sexes. Partial correlations and stepwise regression (controlling for sex; p < 0.05) calculated relationships between the leg tuck with the other tests. Male trainees outperformed females in all tests (p ≤ 0.003). The largest difference was for the BOMBT (d = 2.59) not the leg tuck (d = 1.28). The strongest leg tuck relationships were with pull-ups (r = 0.790) and push-ups (r = 0.553). Sex, pull-ups, and push-ups predicted the leg tuck (r2 = 0.674). Approximately 80% of the females could complete one leg tuck, although female personnel may require specific strength and power training. Pulling strength may be a determining factor in leg tuck performance, which is likely not indicated by the plank.
Keywords: Army Combat Fitness Test; Illinois agility test; abdominal strength; backwards overhead medicine ball throw; between-sex differences; females; firefighters; pull-ups; push-ups; tactical.